Questions tagged [electron]
Anything related to the behavior and properties of electrons, i.e. the elementary subatomic particles accounting for electrical conduction in most solid materials, especially metals.
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Effective Mass of Electrons
In electronics, the fact that mobility of electrons is higher than the mobility of holes is frequently used. How can we explain this using effective mass of electrons and holes ?
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What is the total charge Q of 1 m³ of copper?
I was wondering if I can calculate the total charge Q of 1 m3 of copper, see my calculation in the picture below. Is this correct?
The correct solution (thanks to the community in the comments below):...
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Reasoning behind the density of free electrons/holes being constant with respect to volume of a semiconductor material
Consider a silicon semiconductor material which is having a cuboid shape of dimensions \$2\times 2\times 1\ \mathrm{cc}\$, suppose the atomic density of silicon is \$10^{22}/\mathrm{cc}\$, so in all ...
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How do receiver circuits differentiate between carrier/signal waves?
I've been told and shown that a receiving antenna will pretty much pick up any signals around itself. You can then filter out the frequency you want in order to do something with it.
What I don't ...
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Can electron microscopes record video of electricity?
Since electron microscopes capture electrons, can they be used to capture electrons moving in a circuit, and have they been used for this?
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Conventional current and electron flow in Arduino
On an Arduino there are some pins named GND, some are 5 V, and so on. If electrons flow from the negative to the positive terminal, then does this mean that they are flowing from GND to one of the ...
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Fermi level of metal
Do metals have fermi level? As we know conduction band and valence band are overlaped for a metal. Does it make any sense for metals to have fermi level?
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Can very small currents be accurately measured using only standard analog electronic components on an IC? [closed]
Let's say, for example, that I have a photodiode, which produces electrons in response to the amount of light.
What is the theoretical lower limit that can be accurately measured only using basic ...
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Is it possible to force charges into one plate of a capacitor?
As we know, a capacitor stores energy, but the net amount of charge in it doesn't change. If an electron enters one plate, another leaves the other plate. If the other plate is floating, the entering ...
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Why don't most electrons hit the anode in a cathode ray tube or electron gun?
In a cathode ray tube or electron gun, electrons liberated from the cathode by thermal emission accelerate towards a ring-shaped anode, from the potential difference between cathode and anode.
If an ...
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Do electrons flow from higher to lower or lower to higher potential?
I have seen countless sites saying electrons flow from higher potential to lower potential, but then again I have seen many saying that electrons flow from lower potential to higher.
I have always ...
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Are vehicle electrical components powered from the negative side?
still trying to get my head around electron flow as opposed to conventional current regarding automotive electrical circuits. There seems to be a ton of conflicting information/advice out there so I'm ...
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How is current the derivative of charge
If electric current is the time rate of CHANGE of charge. Then if I have a DC fixed current flowing into a resistor, same amount of charge is always flowing to that resistor, hence the derivative of ...
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The probability that an electron occupies the fermi level at 0K
I was trying to find the probability that an electron occupies the Fermi level at 0K.
Fermi function: {exp[(E-Ef)/kT] + 1}-1;
(k = 8.314 J/mol/K)
According to my calculations, the answer would be 0.5.
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3 Phase Motor to DC Output
In a standard car alternator there is are 3 diodes that keep each of the phases from ever pulling electrons.
There is then a capacitor to smoothens it all out.
However how is it possible that the ...
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KCL when rate of electron flow is given ; To include electron sign or not
Q) We have to determine the I. Magnitude of electron charge is 1.6 x 10^-19C.
I have fundamental confusion in this problem. Should we consider the negative charge of electron while doing the problem. ...
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Generation of electrostatic induction
I need to generate a 500 volt electrostatic charge.
How can I do this?
I don't have a Van de Graaff generator.
What are some practical suggestions?
Basically I want to do an experiment in which I need ...
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Repelling charges and current flow
The electrostatic force between two like charges is repelling. This concept is fairly clear to me with Coulomb's law and electric fields. So two electrons will repel each other. Given this statement, ...
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Why are low band gap semiconductors (like silicon) not ideal for most solar cells? Are their atoms ionized by higher-energy photons?
Most sources on the web say that 1.3 eV or 1.4 eV is 'ideal' for most solar cells...
What happens to lower-gap, gapless or overlap materials (conductors)? Are they ionized, rather than sending their ...
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Why is there EMF present when there is no current?
Current means the rate of flow of charge. Electrons are the ones that carry charge in current.
From the definition of EMF (electromotive force),
When no current is drawn from cell, the potential ...
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What does charge on an electron mean?
As I have read , charge is electrons , protons or neutrons.
Now , according to definition of current , current is the rate of flow of charge I.e flow of electrons. Then , I=Q/t . Unit of Q is coulomb &...
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Majority Charge carriers and electron holes
Suppose I have an extrinsic semiconductor made of silicon and doped with phosphorous. Now, phosphorous has one more electron than silicon. After replacing one silicon atom, and taking its place, the ...
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Shelly 1 Configuration
I am trying to implement the Shelly 1 switch for an electronic device I have. The electronic device has an open collector output channel (AUX1). It also has two output pins Z8 and C.
When Z8 and C are ...
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Can current flow from positive to positive in real life
How to implement a circuit diagram where there are 2 batteries and negative to negative have load and postive to positive have some load. How to implement, like build in real life this ...
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Is there a mnemonic to remember direction of current flow?
I have always stumbled when remembering which current flow notation to use. In my mind, it's by default conventional current flow.
But, I also have in mind electron flow notation.
Do you know of a ...
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How many newtons are there in one coulomb of charge?
Or, I should have said, how many newtons of force does one coulomb of charge exert? At a distance, presumably, of one meter? Since N/C is supposedly equivalent to V/m?
P.S. What are the values for a ...
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Removing collected charges in a IC CMOS circuit exposed under a 30keV electron beam source
I would like to know if there is any mechanism (for example UV light exposition) to remove charges collected in an IC CMOS circuit that was exposed under a 30keV electron beam source. Presumably, ...
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Can a floating capacitor terminal be used to collect electrons?
I want to collect charge from an electron beam source. For that, I'm proposing to put a floating capacitor with its bottom terminal floating and directly exposed to the electron beam gun. The top ...
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Why does current continue flowing in a circuit?
Sorry for the amateur question, but I'm having trouble understanding this phenomenon.
In a closed circuit, electron current flows from the negative terminal of a battery to the positive terminal.
But ...
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Signal interference in receiving antenna?
I’ve been scouring the interweebs for some insight into how electrical signals travel in a wire.
More specifically, I cannot wrap my head around how a receiving antenna works with hundreds if not ...
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In which direction do electric signals flow?
We know that electrons move from the negative to positive terminal, and that holes flow in the conventional direction of current - from the positive to negative terminal.
I've always assumed that this ...
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Electrons flow in Li-ion Battery
I’m new to electricity, and I’ve got a question about electrons flow inside a Li-on battery. A lot of articles and videos show us only Li+ ion flows from anode to cathode through electrolyte during ...
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How do I make a “directed” spark gap?
(Originally asked on engineering StackExchange, I was directed to ask it here)
For a project, I need to create a spark gap that only triggers when there is a conducting material between the 2 contacts....
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How does a single phase shared neutral circuit actually work, physically?
Okay so this is a two part question. First Question is probably more of an ELI5 question. But I am a fairly experienced electrician (NOT AN ENGINEER mind you.) but I have a generally good working ...
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How can electrons in a tungsten filament release infrared light photons?
I have a question regarding electric circuits, specifically when it comes to converting electromagnetic energy into light in a light bulb (tungsten)filament. How can an electron in a tungsten atom of ...
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Mobility of electrons vs holes in semiconductors (intrinsic vs extrinsic)
I was reading my class notes and it was written that electrons are more mobile than holes because the effective mass of electrons are lower than that of holes. (μ=eτ/m*)
I checked online to find the ...
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What does the fermi-level increase in reverse-bias?
Fermi-level tells us the probability of finding an electron at 50%. When you look at an energy band diagram in reverse-bias you can see the Fermi-level increases in the p-type semi-conductor. Why does ...
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In an energy band diagram why is the valance band in the p-type have more energy then n-type?
I am having trouble understanding energy band diagrams. In an energy band diagram of a semi-conductor during equilibrium the valence band of the p-type is higher then n-type meaning electrons in the ...
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Why does a p-type conduction band have higher energy then n-type conduction band in a p-n junction?
In an energy band diagram that represents the p-n junction (during equilibrium) the p-type conduction band has greater energy then an n-type conduction band. Why does the p-type have greater energy ...
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Geometric information within 1D streams of electrons/photons
How is light—or actually any frequency in the EM spectrum—self-encoding and self-modulating 3D info in its 1D self, so that it “knows,” once it strikes a surface, to discharge all the data perfectly ...
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60 GHz radiation
I have always gotten great answers on this site so I thought I'd give this one a shot. In looking into 5G technology, I found that it radiates at 60 GHz, which apparently is in the oxygen absorption ...
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Why Protons travel through the membrance but electrons travel through the wire?
In the case of having two electrodes (anode and cathode). I will always hear that positive ions will jump from one electrode to the other causing the electricity to flow the wire. How come only ...
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What actually happens to electrons in a circuit when work is done at a component?
As the title. Between when voltage is higher; before the electrons reach the component, and afterwards.
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What are the typical paths of holes and electrons in an unbiased PN junction?
Can anyone tell me the typical paths of holes and electrons in an unbiased PN junction at equilibrium? In terms of diffusion currents, is that only holes (majority carriers in the the P-Type) ...
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logic gates. What makes it what it is? [closed]
Does anyone know what it is about each logic gate that makes it "and, or not xand, etc." like, is it a different shape, therefore causing electrons to go different places when a charge is ...
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Does hole concentration fall below the intrinsic concentration, if Si is doped with pentavalent impurities?
If we increase N type doping in a pure Silicon then according to the equation
$$P_n=\frac{n_i^2}{N_D}\text.$$
Then mathematically, hole concentration is less than \$n_i\$, if \$N_D>n_i\$.
Why does ...
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How do capacitors in series work?
If capacitors are connected in series with a vltg source, then how would each plates get the polarity? For a single capacitor, the electrons from one plate are pumped by the source towards the other ...
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Metal semiconductor Junction
As we know in normal p-n junctions is formed by doping on a single semiconductor so that material continuity is maintained which facilitates the movement of charge carriers between two regions. But in ...
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Movement of electron in ac current
Movement of electron direction in ac current is continuously changing which leads to more collision of electrons then dc current.From this can we conclude that ac current heated the wire more than dc ...
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Antenna Theory and Electron Paramagnetic Resonance
Hi I am trying to understand why and how Antenna Theory works as it does.
I can only link Antenna Theory to Electron Paramagnetic Resonance @ 2.8Ghz but I do not know how I can link the resonant ...
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